Process for breaking petroleum emulsions



UNITED STATES PATENT OFFICE PROCESS FOR BREAKING PETROLEUM EMULSIONSMelvin De Groote, University City, Bernhard 'Keiser, Webster Groves,Leonard L. Faure, Kirkwood, and Arthur F. Wirtel, "Webster Groves, Mo.,assignors to The Tret-O-Lite Company, Webster Groves, Mo., a.corporation of Missouri No Drawing. Original application March 16,

1936, Serial N0. 69,222- ,Divided and this allplica-tion March 15, 1937,Serial No. 130,894

4 Claims. (01. 196-4) This invention relates to the treatment of couldanticipate or foresee this unusual effective emulsions of mineral oiland water, such as peness. Apparently, this marked improvement istroleum emulsions, for the purpose of separating not directly related tooil or water solubility, inthe oil from the water, our presentapplication sofar that similar neutralization with other 5 being adivision of our application, Ser. No. amines may yield compounds whichhave a 5 69,222, filed March 16, 1936. greater solubility in oilymaterials or in water,

Petroleum emulsions are of the water-in-oil and yet are not nearly assuitable and not nearl type, and comprise fine droplets of naturallyasefiective in their demulsifying action. occurring waters or brines,dispersed in a more or Apparently, there is some unlocked-for coop--less permanent state throughout the oil which eration or chemical orphysical-chemical rela- 10 constitutes the continuous phase of theemulsion. tionship between the eycl y m n r sidu 4 They are obtainedfrom producing. wells and from and the sulfo-aromatic residue. Theneutralizathe ottom of 011 storage tanks, and are comtion of otherconventional acidic demulsifying .1 monly referred to as cut oil, roilyoil, emulreagents w h y l xy n es-n seem to .15 sified oil and bottomsettlings, produce any marked improvement over the correl The object ofour invention is to provide a sp din sQdlum-Qr' mm s lts, nd in novel.and inexpensive process for separating e. ye .y ehinferior p thusindiemul ions of the charac er referred tointo their e t pp t y the i ed value does component p sofofl and water or brine. not reside in anadditive effect, due to the cycle-" Briefly described, our processconsists insubhexylamine residue; t o the effective 20'jectinga"petroleum emulsion f the water-i il ness of cyclohekylamineapparently is not -en- ';jtype to the. a ction of a treating agent ordemulsi-. j ye y Various other amines Which e Shme "tying agent of thekind hereinafter. described, similarity to this material, Such. as nethereby causing the emulsion to break down'anddg p p am d a am na t Inother separate into its component parts ofoil and water- Words. i the hip yky nap ale 25.

' or brine, when the emulsion is permitted to, re- I ,,sul'fon'ic acidswhichare employed to produce the main me quiescent state after"treatment, or is t at ng agent rfd uls yine a ent us d n u subjected toother equivaleht separatory procepreeessiare neutralized w m y other pdures, ently kindred amines, one .does not obtain a'rer The treatingagent or demulsifying agent conagent that even begins t app o theefiective- 0 templated -by our process consists of or comness of-thedemulsifying agent used in our procprises a cyclohexylamine salt of apoly-alkylated ess. Similarly, if one neutralizes other sulfonicnaphthalene sulfonic' acid in which there ar acids, which are known tobe effective demulsifypresent at least two diflerent alkyl groups, eachs ta s s petroleum sulfenie acids of I one containing at leastthree'carbon atoms and the mahogany acid yp W y yl 35 not more than tencarbon atoms. su h co one does not obtain a more effectivedemulsifypounds are nuclear substituted products. a n indeed, One ismore likely to Commercial demulsifying agents employed for tain ademulsifying agent which is less effective. breaking or resolving oilfield emulsions include, Based on the results of actual tests obtainedin a 40 among other substances, substituted polycyclic Variety Ofemulsified es oeeulringin a nu 40 aromatic sulfonic acids, or theirsalts. The type ber of the major Oil fie s 0f the United ates, whichfinds most frequent application is obtained the conclusion one mustinevitably reach is, that 'byfintroducing one, two or,.more alkyl groupsinto the result obtained by uniting the two residues, "a naphthaleneresidue and then producing the i. e., the cyclohexylamine residue andthe desulfonic acid. Due to the corrosiveness of the scribedsulfo-aromatic residue in a single mole- 45 sulfonic' acid, it is theusual practice to employ, v(Jule, results in an unloeked-for, unique qy, the reagent in the form of a salt, such as amwhi h could not beforeseen by the Present monium salt, potassium salt,,sodium salt, etc.knowledge o the art, a Which p uce a de- We have discovered that if apoly-alklated mulsifyi agent that is particularly ect e for naphthalenesul fpnic acid of the kind hereinafter a large nu ber of emulsifiedcrude oils. 50

described is ine'utreliz d with cyclohexylamine, ly y d aph nes lf nicacids are one obtains a reagent of unusual eifectiveness. producedcommercially, and the salts are used for There does not appear to be anysuitable explanaa variety of purposes. They are generally-pro tion ofthis unusual superiority, and similarly, duced from naphthalene, becausethere does not there does not seem to be any basisby which one appear tb y advantage in the use Of p 55 thalene derivative, such aschlor-naphthalene, alpha and beta naphthol, etc. In other words, onecould introduce the sulfonic acid residue and the alkyl residues into asubstituted naphthalene,

such as chlor-naphthalene, etc., just as readily perhaps as in the caseof naphthalene. However, such derivatives are more expensive and noadvantage is obtained. Such simple derivatives, of course, are thechemical equivalent of naphthalene in the manufacture of such sulfonicacids as are employed in the manufacture of the present reagent. It isunderstood that the word naphthalene is hereinafter employed to includethese derivatives, although, as pointed out, there is no advantage inusing them, and the expense usually would be prohibitive.

The general process of manufacturing the demulsifying agent contemplatedby our process, consists in converting the naphthalene into either thealpha or beta naphthalene sulfonic acid, or in some instances, into adior even a tri-sulfonic acid. In most instances there is no advantagein introducing more than one sulfonic acid residue. In many instances itis unnecessary to use particular care to prepare either only the alphasulfonic acid, or either only the beta sulfonic acid, because a mixturein which either one or the other predominates, or a mixture in which thealpha and beta sulfonic acids are present in approximately equalamounts, is just as satisfactory as one sulfonic acid completely freedfrom the other ype.

The alcohol employed, such as propyl alcohol, butyl alcohol, amylalcohol, hexyl alcohol, decyl alcohol, etc. is converted into the acidsulfate, such as propyl hydrogen sulfate. The naphthalene sulfonic acidand the alkyl hydrogen sulfates are combined in proportions so that two,three, or even four alkyl groups are introduced into the, aromaticresidue. This condensation reaction is generally carried out in thepresence of an excess of sulfuric acid. In some instances, thevariousreactions, such as sulfonation, sulfation, condensation, etc. arecarried out simultaneously. Generally speaking, the di-alkylated andtri-alkyiated material appear to yield the most desirable type ofreagent.

It is obvious, of course, that the alkylated groupsintroduced might bederived from oleflnes,

such as butylene, propylene, amylene, etc., insofar that such olefinesreact directly with sulfuric acid, to produce the alkyl hydrogensulfates. Of course, in addition to introducing such alkyl residues ofthe kind described into the aromatic nucleus, one could also introducean alkyl residue from some other alcohol, as, for example, an

alkylated group derived from ethyl or methyl alcohol, or one mightintroduce a group derived from an aryl, aralkyl, .or cyclo-alcohol, butregardless of whether or not one introduces such other residues, it isnecessary that at least two different alkyl residues of the kinddescribed, i. e., having at least three carbon atoms and not more thanten carbon atoms, be introduced into the naphthalene ring. Suchcompounds having some other residue present, such as a methyl residue,might be considered as being derived from methyl naphthalene, instead ofnaphthalene, and thus, would fall within the class of chemicalequivalents previously noted. It is immaterial as to the particularalcohol employed, or the particular isomeric form of the alcoholemployed, although g'enerallyspeaking, it is most desirable to use theone lowest in cost. It is immaterial whether one uses normal propylalcohol or isopropyl alcohol.

It is immaterial whether one uses a normal butyl or isobutyl alcohol. Itis immaterial whether the alcohol be a primary alcohol, or a secondaryalcohol, or a tertiary alcohol, or the like.

It is obvious that a large number of isomers can be produced in themanufacture of the re- 1 agent employed in the present process. Forinstance, although the sulfonic group may be introduced into either thealpha or beta position, it is manifest that the alkyl groups can beintroduced into various positions in regard to the position of thesulfonic acid residue. Apparently, as far as we are aware, one isomericform is as effective as the other. Reference to the compounds is notintended to indicate any particular isomer, unless the text clearlyindicates some specific position.

Insofar that the most readily available alcohols, from the standpoint ofcost, are isopropyl alcohol, normal butyl alcohol, isobutyl alcohol, andamyl alcohol, it is our preference to produce our reagents from thesealcohols, and it is also essential that the reagent employed in thepresent process be such a kind that at least two different alkyl groupsor residues are introduced into the same sulfa-naphthalene residue.Obviously, two alkyl groups of the same kind may be introduced providedthere is at least one more alkyl group of a diflerent kind alsointroduced into the aromatic nucleus.

In the actual manufacture of alkylated naphthalene sulfonic acids, thecompletion of the desired chemical reactions is followed by a washingprocess which removes the excess of sulfuric acid or other sulfonation,sulfation, or condensation reagent employed. The acidic mass thusobtained is neutralized with cyclohexylamine in the same manner thatsodium or potassium or ammonium hydroxides might usually be employed.The final product, if it represents a pasty or semisolid .or a solidmass, is rendered suitable for industrial use by the addition of asolvent, such as water, an alcohol, a coal tar solvent,'a petroleumhydrocarbon solvent, or in any similar manner.

The demulsifying agent that we prefer to use in practising our processis obtained by a reaction in which two moles of isopropyl alcohol andone mole of normal butyl alcohol are'united with one mole of naphthaleneby the customary sulfation, sulfonation and condensation reactions.Generally speaking, it is easier to conduct the reaction so that thebulk of the sulfonic acid represents/the beta type, although the alphatype may be produced. if desired. The neutralized.

product is diluted with one or more solvents, so as to reduce itsviscosity to 'that of ordinary castor oil, or slightly greater. Thesolvents which we preferably employ are a mixture of two or more of thefollowing: Water, denatured alcohol, kero sometimes some variation innomenclature in regard to the salts derived from strong acids andvarious amines. For instance, the combination of aniline, andhydrochloric acid, is often referred;

When aniline hy-ia 1 to as aniline hydrochloride. drochloride is treatedwith caustic soda, aniline is regenerated and sodium chloride formed.For this reason, and perhaps for other reasons, structural conditionsare best expressed by referring to the compound as a hydrochloride, inorder to indicate that one does not obtain the chloride of a quarternaryammonium compound. Similarly, the reaction of cyclohexylamine with asulfonic acid may be considered as producing the cyclohexylamine. salt,although for reasons pointed out, such salt might be looked upon as acyclohexylamine hydrogen sulfonate, as well as being considered as acyclohexylamine sulfonate. Insofar that it is perfectly clear as to thechemical composition of the compound, it is immaterial whichnomenclature is employed.

In such instances where there is present more than one sulfonic acidresidue, as in the formation of a di-sulfonic acid, or a tri-sulfonicacid,

if desired, all the sulfonic acid hydrogen may be neutralized withcyclohexylamine, or if desired, only one sulfonic hydrogen may beneutralized with cyclohexylamine, and the other sulfonic hydrogen atomor atoms may be neutralized with some other suitable base, such assodium hydroxide, potassium hydroxide, ammonium hydroxide, etc.

cyclohexylamine salts, such as the hydrochloride, may react by doubledecomposition with alkali salt sulfon'ates in a suitable medium toproduce the cyclohexylamine sulfonate.

Conventional demulsifying agents employed in the treatment of oil fieldemulsions are used as such, or after dilution with any suitable solvent,such as water, petroleum hydrocarbons, such as gasoline, kerosene, stoveoil, a coal tar product, such as benzene, toluene, xylene, tar acid oil,cresol, anthracene oil, etc. Alcohols, particularly aliphatic alcohols,such as methyl alcohol, ethyl alcohol, denatured alcohol, propylalcohol, butyl alcohol, hexyl alcohol, octyl alcohol, etc., may beemployed as diluents. Miscellaneous solvents, such as pine oil, carbontetrachloride, sulfur dioxide extract obtained in the refining oipetroleum, etc. may be employed as diluents. Similarly, thematerial ormaterials employed as the demulsifying agent of our process may beadmixed with one or more of the solvents customarily used in connectionwith conventional demulsifying agents. Moreover, said material ormaterials may be used alone or in admixture with other suitable wellknown classes of demulsifying agents, such as demulsifylng agents of themodified fatty acid type, the petroleum sulfonate type, the alkylatedsulfo-aromatic' type, in which the sulfonic hydrogen is neutralized bythe use of some base other than cyclohexylamine.

It is well known that conventional demulsifying agents may be used in awater-soluble form, or in an oil-soluble form,'or in a form exhibitingboth'oil and water solubility. Sometimes they may be used in a formwhich exhibits relatively limited water solubility and relativelylimited oil solubility. However, since such reagents are sometimes used,in a ratio of 1 to 10,000, or 1 to 20,000, or even 1 to 30,000, such anapparent insolubility in oil and water is not significant, because saidreagents undoubtedly have solubility within the concentration employed.This same fact is true in regard to the material or materials employedas the demulsifying agent of our process.

Having thus described our invention, what we claim as new and desire tosecure by Letters Patent is:

1. A process for breaking petroleum emulsions v of the water-in-oiltype, which consists in subjecting the emulsion to the action of ademulsifylng agent comprising a cyclohexylamine salt of a poly-alkylatednaphthalenesulfonic acid in which there are present at least twodifferent alkyl groups, each one containing at least three carbon atomsand not more than ten carbon atoms.

2. A process for breaking petroleum emulsions of the water-in-oil type,which consists in subjecting the emulsion to the action of ademulsifying agent comprising a cyclohexylamine salt of a poly-alkylatednaphthalene sulfonic acid containing at least one propyl group and atleast one butyl group.

3. A process for breaking petroleum emulsions of the water-in-oil type,which consists in subjecting the emulsion to the action of ademulsifying agent comprising a cyclohexylamine salt of l apoly-alkylated naphthalene sulfonic acid containing at least one propylgroup and at least one amyl group.

4. A process for breaking petroleum emulsions of the water-in-oil type,which consists in subjecting the emulsion to the action of ademulsifying agent comprising a cyclohexylamine salt of a poly-alkylatednaphthalene sulfonic acid containing at least one butyl group and atleast one amyl group.

MELVIN DE GROOTE. BERNHARD KEISER. LEONARD L. FAURE. ARTHUR F. WIR'I'EL.

